This invention relates to multiple input, single output, mechanical actuators which are particularly useful in connection with governors for engines or the like but not limited thereto.
A variety of mechanical apparatus utilize control mechanisms wherein a single output to the mechanism being controlled is provided by the control mechanism in response to any one or more of a plurality of input signals to the control mechanism. Such control mechanisms perform a so-called logical OR function and typically receive input signals of the same medium. For example, each input signal may be a pressurized air signal or a pressurized hydraulic fluid signal, but not both. The input signals may be in the form of electrical signals or in the form of movement of mechanical elements as well. Seldom, if at all, are input signals of different mediums utilized by a single, multiple input, single output actuator and, in many cases, it is required to convert an input signal from one medium to another prior to its application to the control device.
For example, an actuator may receive a pneumatic signal from a source of air under pressure and the apparatus controlled may also generate, as by means of a mechanically operated switch, an electrical signal. The electrical signal is converted to the air medium through the use of a solenoid operated valve prior to its application to the actuator.
Moreover, such actuators are typically designed for a predetermined number of inputs and where a particular apparatus to be controlled requires a greater or lesser number of inputs to the control device, a wholly different actuator must be employed, or input capacity wasted, or multiple actuators utilized, or combinations of the foregoing.